Make GetTermVersionAction internal

GetTermVersion action has been added to check if cluster state needs to
be updated as a performance improvement on all cluster state checks.
The Authorization systems in the Security Plugin check all actions that
do not start with `internal:` for permissions causing users without
`cluster:monitor/*` permissions to start getting 403 exceptions.

This change signals that this action does not require an authorization
check by any security systems since it cannot be called via REST APIs.

Signed-off-by: Peter Nied <petern@amazon.com>

Author: peternied

server/src/main/java/org/opensearch/action/admin/cluster/state/term/GetTermVersionAction.java

@@ -18,7 +18,7 @@
 public class GetTermVersionAction extends ActionType<GetTermVersionResponse> {
 
     public static final GetTermVersionAction INSTANCE = new GetTermVersionAction();
-    public static final String NAME = "cluster:monitor/term";
+    public static final String NAME = "internal:monitor/term";
 
     private GetTermVersionAction() {
         super(NAME, GetTermVersionResponse::new);

server/src/test/java/org/opensearch/action/support/clustermanager/TransportClusterManagerTermCheckTests.java

@@ -223,7 +223,7 @@ public void testTermCheckMatchWithClusterManager() throws ExecutionException, In
         assertThat(transport.capturedRequests().length, equalTo(1));
         CapturingTransport.CapturedRequest capturedRequest = transport.capturedRequests()[0];
         assertTrue(capturedRequest.node.isClusterManagerNode());
-        assertThat(capturedRequest.action, equalTo("cluster:monitor/term"));
+        assertThat(capturedRequest.action, equalTo("internal:monitor/term"));
         GetTermVersionResponse response = new GetTermVersionResponse(
             new ClusterStateTermVersion(
                 clusterService.state().getClusterName(),
@@ -249,7 +249,7 @@ public void testTermCheckNoMatchWithClusterManager() throws ExecutionException,
         assertThat(transport.capturedRequests().length, equalTo(1));
         CapturingTransport.CapturedRequest termCheckRequest = transport.capturedRequests()[0];
         assertTrue(termCheckRequest.node.isClusterManagerNode());
-        assertThat(termCheckRequest.action, equalTo("cluster:monitor/term"));
+        assertThat(termCheckRequest.action, equalTo("internal:monitor/term"));
         GetTermVersionResponse noMatchResponse = new GetTermVersionResponse(
             new ClusterStateTermVersion(
                 clusterService.state().getClusterName(),